1. Field of the Invention
The present invention relates to an adjustment system in an automatic transmission for an automobile.
2. Description of the Related Art
There has been known such automatic transmission as shown in FIG. 9, the transmission which described in a bullet of the Japanese Patent Laid-Open No. 141523/1993, for example. The automatic transmission 101 shown in FIG. 9 mentioned above comprises an actuator 103, a shift operating unit 105, a rotation position detecting unit 107 and a controlling unit 109.
The actuator 103 comprises an electric motor and is connected to a driving circuit 111 connected to the controlling unit 109. The actuator 103 rotates a manual shaft 113 so as to switch a shifting position. The shift operating unit 105 comprises a selecting switch and instructs a shifting position to output an instruction signal to the controlling unit 109. The rotation position detecting unit 107 comprises, for example, a potentiometer and detects a rotation angle of the manual shaft 113 to input a detection signal to the controlling unit 109. The controlling unit 109 receives the instruction signal from the operating unit 105 to output the signal to the driving circuit 111 until the rotation position detected by the rotation position detecting unit 107 accords with the instructed shifting position, and controls and drives the actuator 103.
Therefore, when an operator operates the shift operating unit 105 to instruct the shifting position, the controlling unit 109 controls the manual shaft 113 to be rotated to the instructed shifting position so that gears of the automatic transmission 101 can be shifted.
When the rotation position detecting unit 107 comprises a potentiometer, the rotation position detecting unit 107 outputs a voltage value, which is schematically proportional to a rotation angle of the manual shaft 113, to detect a rotation angle. The rotation position detecting unit 107 is mounted such that a point of a voltage value corresponding to a point N (neutral range) of the rotation position detecting unit 107 would accord with a position of the neutral range N of the manual shaft 113. Thus, in the case that rotation of the manual shaft 113 changes the shifting position, such as P (parking range) and D (driving range) can be detected by means of a voltage value outputted by the rotation position detecting unit 107 .
In such mounting, however, the point N of the potentiometer is likely to be different from that of manual shaft due to wrong mounting. Further, dispersion of a resistance value of the potentiometer itself in manufacturing is likely to make a difference between a resistance value corresponding to each shifting position and a design value. Moreover, there is also likely to be a little difference in respective gear position from the design value due to individual difference of the automatic transmission 101.
The invention is aimed to provide an adjustment system in an automatic transmission capable of learning a relation between the shifting position and an output value of the rotation position detecting unit after mounting thereof in a simple construction.
An invention according to a first aspect is concerned with an adjustment system in an automatic transmission including: an electric actuator for switching a shifting position by rotating a manual shaft; a shift operating unit for instructing the shifting position to output an instruction signal; a rotation position detecting unit for detecting a rotation angle of the manual shaft on the basis of an output signal corresponding to the rotation angle; a locating unit, which is provided with a concave and convex portion corresponding to the each shifting position, for locating the manual shaft by a detent pin getting over a convex to be fitted in a predetermined concave in shifting; and a controlling unit for driving and controlling the actuator until a rotation position, which is detected by the rotation position detecting unit in response to the receipt of the instruction signal from the shift operating unit, accords with the instructed shifting position, wherein the adjustment system comprises an electric current detecting unit for detecting a driving current of the actuator; a shifting position calculating unit for calculating a shifting position of the manual shaft on the basis of detection by the electric current detecting unit of a change in the driving current of the actuator at the time when the detent pin gets over a convex to be fitted in a predetermined concave in shifting described above; and rotation position detection learning unit for learning a relation between the shifting position calculated by the shifting position calculating unit and an output value of the rotation position detecting unit.
An invention according to a second aspect is concerned with the adjustment system in an automatic transmission according to the first aspect, wherein the electric current detecting unit detects a change in a driving current at the time when the manual shaft is rotated back and forth so that the actuator can switch all the shifting positions back and forth, and the shifting position calculating unit calculates all the shifting positions on the basis of the change in the driving current.
An invention according to a third aspect is concerned with an adjustment system in an automatic transmission including: an electric actuator for switching a shifting position by rotating a manual shaft; a shift operating unit for instructing the above-mentioned shifting position to output an instruction signal; an inhibitor switch for detecting the shifting point; a rotation position detecting unit for detecting a rotation angle of the manual shaft; and a controlling unit for driving and controlling the actuator until a rotation position, which is detected by the rotation position detecting unit in response to the receipt of the instruction signal from the shift operating unit, accords with the instructed shifting position, wherein the adjustment system comprises a shifting position calculating unit for calculating a shifting position of the manual shaft on the basis of an output of the inhibitor switch in shifting; and a rotation position detection learning unit for learning a relation between the shifting position calculated by said shifting position calculating unit and an output value of the rotation position detecting unit.
An invention according to a fourth aspect is concerned with the adjustment system in an automatic transmission according to the third aspect, wherein the shifting position calculating unit calculates at least one shifting point of the manual shaft on the basis of rising and falling outputs of the inhibitor switch at the time when the actuator rotates the manual shaft so as to switch at least one shifting position.
An invention according to a fifth aspect is concerned with the adjustment system in an automatic transmission according to the third aspect, wherein the shifting position calculating unit calculates all the shifting positions of the manual shaft on the basis of rising and falling outputs of the inhibitor switch at the time when the actuator rotates the manual shaft so as to switch all the shifting positions.
In the invention according to the first aspect, when the shift operating unit instructs a shifting position, an instruction signal is inputted to the controlling unit, which drives and controls the actuator, so that the manual shaft would be rotated and driven to the instructed shifting position. When the rotation position of the manual shaft, which is detected by the rotation position detecting unit, accords with the shifting position instructed by the shift operating unit at that time, driving and controlling of the actuator are stopped and the manual shaft stays in the instructed shifting position. The detent pin, which is the locating unit, gets over a convex in shifting to be fitted in a predetermined concave corresponding to the shifting position, so that the manual shaft can be located. In such automatic transmission, the electric current detecting unit detects a driving current of the actuator and the shifting position calculating unit can calculate the shifting position of the manual shaft on the basis of a change in the driving current of the actuator at the time when the detent pin gets over a convex to be fitted in a predetermined concave in shifting. The rotation position detection learning unit can learn a relation between the shifting position calculated by the shifting position calculating unit and an output value of the rotation position detecting unit.
Therefore, the shifting position calculating unit can solve wrong mounting and calculate the shifting position of the manual shaft so that the output value of the rotation position detecting unit at the calculated shifting position would be the shifting position detected and outputted by the rotation position detecting unit. Thus, the shifting position of the manual shaft can be correctly corresponded to the output value of the rotation position detecting unit in a relation therebetween regardless of wrong mounting, dispersion of a resistance value of the rotation position detecting means in manufacturing, and individual difference of the automatic transmission, so that correct shifting can be achieved.
In the invention according to the second aspect, in addition to the effect of the invention according to the first aspect, the electric current detecting unit detects a change in the driving current at the time when the actuator rotates the manual shaft back and forth so as to switch all shifting positions back and forth, and the shifting position calculating unit can calculate all the shifting positions on the basis of the change in the driving current. Therefore, a relation between all the shifting positions calculated by solving such as wrong mounting and the output value of the rotation position detecting unit can be learned, so that more correct shifting can be achieved.
In the invention according to the third aspect, when the shift operating unit instructs the shifting position, an instruction signal is inputted to the controlling unit and the actuator is driven and controlled so that the manual shaft would be rotated to the instructed shifting position. When the rotation position detecting unit detects a rotation angle of the manual shaft at that time and the rotation position detected by the rotation position detecting unit accords with the instructed shifting position, driving and controlling of the actuator are stopped and the shifting is completed. The inhibitor switch detects the shifting position. In such automatic transmission, the shifting position calculating unit can calculate the shifting position of the manual shaft on the basis of an output of the inhibitor switch in shifting and the rotation position detection learning unit can learn a relation between the shifting position calculated by the shifting position calculating unit and an output value of the rotation position detecting unit. Thus, the relation between the shifting position of the manual shaft and an output value of the rotation position detecting unit can be correctly learned regardless of wrong mounting, dispersion of a resistance value of the rotation position detecting unit in manufacturing, and individual difference of the automatic transmission, so that correct shifting can be achieved.
In the invention according to the fourth aspect, in addition to the effect of the invention according to the third aspect, the shifting position calculating unit can calculate at least one shifting position of the manual shaft on the basis of rising and falling outputs of the inhibitor switch at the time when the actuator rotates the manual shaft so as to switch at least one shifting position. The relation between all the shifting positions and the output value of the rotation position detecting unit can be learned on the basis of the above at least one shifting position. Thus, correct shifting can be achieved.
In the invention according to the fifth aspect, in addition to the effect of the invention according to the third aspect, the shifting position calculating unit can calculate all the shifting positions of the manual shaft on the basis of rising and falling outputs of the inhibitor switch at the time when the actuator rotates the manual shaft so as to switch all the shifting positions. Thus, the relation between all the shifting positions calculated and the output value of the rotation position detecting unit can be learned, so that more correct shifting can be achieved.